The present disclosure relates generally to emergency access in communication networks and more specifically to a system and method for provisioning multimedia emergency access contact information in a wireless network.
As used herein, the terms wireless local area network (WLAN) device and wireless device can refer to wireless devices such as mobile telephones, personal digital assistants, handheld or laptop computers, and similar devices or other user agents (UAs) that have telecommunications capabilities and are configured to communicate using a packet-switched (PS) network, for example, Bluetooth, Zigbee, UWB, WiMAX and any cellular technology. In some embodiments, a WLAN device may refer to a mobile, wireless device. The term WLAN device may also, in some cases, refer to devices that have similar capabilities but that are not generally transportable, such as desktop computers, set-top boxes, or network nodes. Throughout this disclosure, WLAN device may also refer to SIP (or similar multimedia communication protocols) devices such as wireless devices, wireless set-top boxes, or other wireless communication devices.
Some WLANs may be configured to provide voice-over-internet protocol (VoIP) services. Using such a network, various WLAN devices may be configured to communicate with one another to deliver voice communications. The WLAN devices may also be configured to communicate with conventional circuit-switched (CS) telephone networks via the WLAN. In addition to voice services, WLAN devices may also use the WLAN to deliver multimedia communications such as video-conference, text-messaging, multimedia messaging services, or other communication services. These networks may be configured to provide interworking information and services—thereby allowing WLAN devices to interwork with external networks, as typically found in hotspots or other networks irrespective of whether the service is subscription based or free. In some cases, interworking aids network discovery and selection, enabling information transfer from external networks, and enabling emergency services.
It is a requirement for VoIP service providers to provide their subscribers with the ability to quickly contact emergency services. Generally, the service providers must provide their subscribers with a single phone number that allows the subscriber to quickly contact local emergency services. The emergency contact number is provided to the subscriber by a hotspot or access device of the network to which the subscriber is connected and is based upon a geographical location of the subscriber—generally, the emergency contact number allows the subscriber to contact emergency services that are located nearby. In some cases, however, the emergency contact number is for a centralized service, which then connects the subscriber to appropriate emergency services. After the centralized control center is contacted, the user's call can be re-routed to a local first provider. This “tier” system is used in several countries and may be the basis of the 3GPP/LTE IMS system, for example. After the subscriber dials the emergency number, the network connects the user to a local public safety answering point (PSAP) associated with the telephone number. The PSAP can then communicate with the subscriber, and dispatch services to assist the subscriber.
In conventional telephone networks, there are several mechanisms for determining the location of a users handset, and, thereby, the most appropriate PSAP for the subscriber. If the handset is connected to a fixed line, for example, the provider may store a record indicating the physical address or location of that fixed line. If, however, the handset includes a cell phone (cellular radio access technology), the provider can determine a coarse location of the handset using the position of the cell transmitter currently communicating with the cell phone. With the location of the handset or cell transmitter close to the handset known, the provider can quickly connect the user to the most appropriate PSAP.
When communicating via a WLAN (e.g., using VoIP services), however, it can be extremely difficult for a service provider to determine a location of the WLAN device. The WLAN device may be connected to the service provider using a WLAN network connection in a first country while the service provider resides in another country. In other cases, the WLAN device may be connected to the service provider through one or more proxies or networks having complicated architectures and using IP addresses that are dynamic and constantly changing. Furthermore, for privacy reasons, in several locations it is illegal to retrieve accurate location information from a WLAN device. As a result, when a WLAN device connects to a service provider, the geographical location of the WLAN device cannot be easily determined. Because it is difficult to determine the location of the WLAN device, the service provider cannot easily ensure that any emergency calls are routed to the most appropriate local PSAP.
To assist the service provider in determining the most appropriate local PSAP (and, consequently, the most appropriate emergency contact number) for a particular WLAN device, existing WLAN systems allow for the updating of emergency call dial-strings, within a WLAN device, from the hotspot prior to the establishment of a user session. Because the hotspot is resident at a fixed location, the hotspot may be provided with the telephone number of an appropriate, geographically close PSAP or a centralized service to be used in the case of an emergency. After receiving the emergency contact number from the hotspot, if the user wishes to make an emergency call, an “emergency” button on the WLAN device is pressed or an emergency number is dialed and the device retrieves the provisioned emergency contact number from a memory. In some cases, multiple emergency numbers may be provided for different emergency services. In that case, the WLAN device may provide multiple emergency buttons for accessing each of the services. After retrieving the emergency contact number, the WLAN device connects to the PSAP identified by the number and the user can place the emergency call. Because the number for the PSAP was retrieved from the WLAN hotspot, the number identifies a local PSAP that can efficiently alert local services to provide assistance.
Existing network configurations, however, are only configured to provision regional emergency call number dial string information. Future, next-generation, 911 services, require that multimedia emergency services be enabled for WLAN devices. Multimedia emergency services would allow a user to make, in addition to emergency phone calls, emergency video calls, or to send emergency text messages, for example. Existing WLAN systems are unable to distribute the emergency contact and routing information necessary for a subscriber to access those services.